visprint- Fractal fingerprint generator.
md5sum (sha1sum) foo.bar | visprint
[Options] > foo.png
Visprint makes cool fractal fingerprint png images based on the contents of any
file. The image will be different for almost every file with even slightly
different contents. Visprint uses the IFS fractal generation process,
pioneered by Michael Barnsley. It is a way to create images which are
self-similar to infinite depths. In other words, the picture is made up of
smaller versions of itself.
Visprint takes a checksum as its input. This is usually a 32-byte number which
is generated from a file. In order to generate the checksum, you will also
need a hash function command such as md5sum or sha1sum.
- Use the given background brightness. 0 means black, 255 means white. You
can try other values, but the resultant image will be quite ugly. The
default is 0 (black).
- Use the alternate coloring method. Flips RGB to BGR.
- Create the fractal with 4 different color areas.
- Create a semi-grayscale image. The output varies heavily depending on the
- Use the given intensity of color. With a black background, a higher
intensity produces a brighter image. With a white background, higher
intensity produces a darker image. In all cases, calculation time doubles
every time you double the intensity. The default is 30.
- Use the given checksum length. Modify this number to match the hash
function you are using. Examples: 32 for md5, 40 for sha1, 64 for sha256,
128 for sha512... The output of 128 is foggy (but still useful). Higher
values will result in crappy images, therefore 128 is the maximum
accepted. The default value is 32.
- Use the given value for both the x and y resolutions. The calculation time
will quadruple every time you double this value. The default is 300.
- Create the image with a transparent background.
- Output version information and exit.
- -?, -h, --help
- Output help information and exit.
- To create a nice 500x500 fingerprint of your kernel type:
- md5sum /boot/mykernel | visprint -r500 > mykernel.png
- Let's say that you want a 100x100 sha1 fingerprint of your website's index
file, with png transparency that looks good on a white background:
- sha1sum index.html | visprint -l -r100 -b255 -t > index.png
- Current Maintainer:
Goizeder Ruiz de Gopegui http://www.tastyrabbit.net/visprint
- Previous Geniuses:
Ian Golderg: http://http.cs.berkeley.edu/~iang/
Raph Leviev: http://www.cs.berkeley.edu/~raph/
Hal Finney: http://www.rain.org/~hal/
David Johnston: http://www.cybercities.com/ston/
Soren Andersen: http://intrepid.perlmonk.org/
The original code was written by Ian Goldberg, based on an idea by Hal
Finney, in a post to the coderpunks mailing list. The most excellent color
enhancements were added by Raph Levien. David Johnston made a port for
Win95 console mode and added a bunch of nice features. Soren Andersen
developed the png and transparency code. Goizeder Ruiz de Gopegui, the
current maintainer, cleaned the code, created the documentation and put
- Copyright 2007 Goizeder Ruiz de Gopegui
- This is free software. You may redistribute copies of it under the terms
of the GNU General Public License.
- There is NO WARRANTY, to the extent permitted by law.